Can the source text for several layers be controlled by one layer?

I have been trying to put this expression in layer 1 and hoping to control layer 5,6 7 etc.

thisComp.layer(5).text = "43"

Needless to say, it doesn't work. Is there something that does?

Thanks. I will check out those sites. I haven't figured out where the documentation is hidden that describes the inner workings of AE. That should give me the answer as to whether I can access the guides. I kind of wish there were something like Photoshop actions in AE. Then it would be simple. :mrg...

I understand JavaScript, and I've done some application scripting like using Python with Blender. But I'm not sure how to get started with AE and JavaScript. I downloaded the Javascript Tools Guide and have been reading through it. For my first application, I want to make a simple bit of code that p...